Herbicidal composition comprising 4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoic esters

ABSTRACT

Herbicidal compositions comprising
     A) at least one compound from the group of the substituted phenylsulfonylureas of the formula I and their agriculturally acceptable salts   

                         
in which
     R 1  is (C 1 –C 8 )alkyl, (C 3 –C 4 )alkenyl, (C 3 –C 4 )alkynyl or (C 1 –C 4 )alkyl which is mono- to tetrasubstituted by radicals selected from the group consisting of halogen and (C 1 –C 2 )alkoxy, and   B) at least one herbicidally active compound from the group of compounds composed of   Ba) herbicides which act selectively against grasses in cereals and/or maize,   Bb) herbicides which act selectively against dicots in cereals and/or maize,   Bc) herbicides which act selectively against grasses and dicots in cereals and/or maize and   Bd) herbicides which act non-selectively against grass weeds and broad-leaved weeds in non-crop areas and/or selectively against grass weeds and broad-leaved weeds in transgenic crops.

This application is a continuation-in-part of application U.S. Ser. No.08/659,721, filed Jun. 6, 1996, now U.S. Pat. No. 5,990,047, whichclaims priority to German application No. 195 20 839.0, filed Jun. 8,1995, both incorporated herein by reference

The invention lies in the technical field of the crop protectionproducts, in particular the invention relates to herbicidal compositionscomprising4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureido-sulfonyl]benzoicesters and/or their salts.

WO 92/13845 (PCT/EP92/00304) discloses iodinated arylsulfonylureas ofthe formula 1 and their salts

the formula 1 embracing a large number of possible individual compoundsdue to the extensive and broad definition of the radicals Q, W, Y, Z, R,R¹, R² and R³.

In the chemical Example 9 of WO 92/13845, methyl2-[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-4-iodobenzoateis synthesized, while the chemical Example 10 relates to the preparationof ethyl2-iodo-3-[[[[4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino]sulfonyl]benzoate.A chemical example of the synthesis of4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoicesters is not described.

Table 3 of WO 92/13845 lists compounds of the formula 2

the Examples No. 7, 44, 81, 118, 155, 192, 229, 237, 245, 253, 261, 269,277, 298, 299 and 300 relating to those compounds of the formula 2 inwhich Y and Z are nitrogen, Q and W are oxygen, R¹ is hydrogen, R² isOCH₃ and R³ is CH₃. However, a melting point is only given in Examples 7(R=methyl) and 44 (R=ethyl) and in Examples 298 to 300 (sodium, lithium,potassium salt; R is in each case methyl).

No biological examples of the compounds listed above individually arementioned in WO 92/13845. Rather, a general mention is made of thepossibility of using the compounds of the formula 1 with otherherbicides. This is followed by an exemplary enumeration of more thanapproximately 250 various standard substances, and amongst thosementioned individually are acifluorfen, alachlor, amidosulfuron,atrazine, bentazone, bifenox, bromoxynil, chlortoluron, chlorsulfuron,dicamba, diclofop-methyl, difenzoquat, diflufenican, fenoxapropethyl,flamprop-methyl, fluoroglycofen-ethyl, fluroxypyr, fomesafen,glufosinate, glyphosate, imazamethabenzmethyl, ioxynil, isoproturon,lactofen, MCPA, mecoprop, methabenzthiazuron, metolachlor, metribuzin,metsulfuronmethyl, pendimethalin, primisulfuron-methyl, terbuthylazine,thifensulfuron-methyl, tralkoxydim, triasulfuron and tribenuron-methyl.Neither information with a view to the purposes of a joint applicationwhich exceed a mere mention of the substances nor, for example, amotivation for the specific choice and combination of certain activesubstances can be found in WO 92/13845.

While most of the iodinated arylsulfonylureas disclosed in WO 92/13845as set forth in formula 1 have a useful to good activity against a broadspectrum of economically important mono- and dicotyledon harmful plantsand while even weeds which occur under the specific conditions of ricegrowing such as, for example, Sagittaria, Alisma, Eleocharis, Scirpus,Cyperus etc., are controlled with the aid of active substances of theformula 1, the individual active substances are frequently insufficientfor controlling the spectrum of mono- and dicotyledon weeds which occursunder realistic agricultural conditions, especially in cereals or maize,but also in other crops.

In the light of the prior art given and discussed herein, it wastherefore an object of the invention to provide novel herbicidallyactive mixtures which allow the grower to control the weed spectrum, orindividual weed species which are difficult to combat, in cereals, maizeand other crop species by means of one application, or a fewapplications, of herbicides. Moreover, the mixtures of herbicidallyactive substances which are known in principle should contribute toclosing so-called “activity gaps” and simultaneously to reduce the ratesof the individual active substances as far as this is possible.

These and other objects which have not been mentioned individually areachieved by herbicidal compositions which are characterized in claim 1.Thus, the invention relates to herbicidal compositions comprising

-   A) at least one herbicidally active substance from the group of the    substituted phenylsulfonylureas of the formula I and their    agriculturally acceptable salts

in which

-   R¹ is (C₁–C₈)alkyl, (C₃–C₄)alkenyl, (C₃–C₄)alkynyl or (C₁–C₄)alkyl    which is mono- to tetrasubstituted by radicals selected from the    group consisting of halogen and (C₁–C₂)alkoxy,-   and-   B) at least one herbicidally active compound from the group of    compounds composed of-   Ba) herbicides which act selectively against grasses in cereals    and/or maize,-   Bb) herbicides which act selectively against dicots in cereals    and/or maize,-   Bc) herbicides which act selectively against grasses and dicots in    cereals and/or maize and-   Bd) herbicides which act non-selectively against grass weeds and    broad-leaved weeds in non-crop areas and/or selectively against    grass weeds and broad-leaved weeds in transgenic crops.

The combinations according to the invention of herbicidally activesubstances of types A and B allow a particularly advantageous control,as required by the grower, of the weed spectrum including evenindividual species which are difficult to combat. Moreover, thecombinations according to the invention allow the rates of the amountsof active substance of the individual components of the combination tobe reduced, which makes possible a more economical solution from thepoint of view of the user. Finally, it was surprising that increasedactivities were achieved which exceed the level to be expected, theherbicidal compositions of the invention thus exhibiting a wide range ofsynergistic activities.

While the phenylsulfonylureas of the formula I which have an iodinesubstitution in the 4-position of the phenyl ring are encompassed inprinciple for example by the formula 1 in WO 92/13845, the prior artdoes not show their outstanding suitability as components in synergisticmixtures with other herbicides. In particular, the prior-art literaturementions nothing about such an exceptional position of the strictlylimited and clearly defined group of the4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureido-sulfonyl]benzoicesters which are optionally present in the form of their salts.

Particularly interesting as type A components for the combinations ofthe invention are compounds of the formula I or their salts in which R¹is methyl, ethyl, nor isopropyl, n-, tert-, 2-butyl or isobutyl,n-pentyl, isopentyl, n-hexyl, isohexyl, 1,3-dimethylbutyl, n-heptyl,1-methylhexyl or 1,4-dimethylpentyl.

In a particularly preferred embodiment, herbicidal compositionsaccording to the invention comprise a type A compound of the formula Ior a salt thereof in which R₁ is methyl.

The type A compounds (formula 1) can form salts in which the hydrogen ofthe —SO₂—NH— group is replaced by an agriculturally suitable cation.Examples of these salts are metal salts, in particular alkali metalsalts (for example sodium or potassium salts) or alkaline earth salts,or else ammonium salts or salts with organic amines. Equally, saltformation can be effected by an addition reaction of a strong acid withthe heterocyclic moiety of the compounds of the formula I. Exampleswhich are suitable for this purpose are HCl, ENO₃ trichloroacetic acid,acetic acid or palmitic acid.

Particularly advantageous type A compounds are those in which the saltof the herbicide of formula (I) is formed by replacing the hydrogen ofthe —SO₂—NH— group by a cation from the group of the alkali metals,alkaline earth metals and ammonium, preferably sodium.

If the compounds of the formula I contain one or more asymmetric carbonatoms or else double bonds which are not specifically mentioned in theformula, they are still type A compounds. The formula I embraces allstereoisomers which are possible and which are defined by their specificspatial form, such as enantiomers, diastereoisomers and Z- andE-isomers, and these can be obtained from the stereoisomer mixtures bycustomary methods or prepared by stereoselective reactions incombination with the use of stereochemically pure starting materials.Thus, the abovementioned stereoisomers can be employed according to theinvention in pure form and in the form of their mixtures.

As a rule, the type B components are standard herbicides which have,however, been selected with certain criteria in mind. Thus, with twoexceptions (subgroup Bd), they are herbicides which act selectively incereals and/or in maize against undesirable plants. The harmful plantsto be controlled include mainly grasses and/or dicots. With a view tothe activity of the type B standard herbicides, in turn, the substancescan be ranked according to the controlled plants on which they focus.Thus, some of the type B herbicides act almost exclusively againstgrasses and others mainly against dicots, while the type B herbicidesfrom subgroup Bc) are employed both against grasses and against dicots.In any case, however, the combinations according to the invention resultin an optimized spectrum of action by complementing and intensifying theherbicidal properties of the type A compounds. Last but not least, thisalso applies to the type B compounds from group Bd), which embraces theherbicides which are active against grass weeds and dicotylden weeds andare non-selective in non-crop areas and/or selective in transgeniccrops.

In a preferred variant, a composition according to the invention ischaracterized in that it comprises, as type B herbicides, one or moreherbicides which act selectively against grasses in cereals and/or inmaize and which are from the group embracing the2-(4-aryloxyphenoxy)propionic acids and their esters, ureas,sulfonylureas, cyclohexanedione oximes, arylalanines,2,6-dinitroanilines, imidazolinones and difenzoquat. Besides theabovementioned individual substances, said classes of chemicals includea series of grass herbicides, which are suitable as components incombinations with type A compounds.

Preferred compositions according to the invention comprise, as type Bherbicides, one or more herbicides which act selectively against grassesin cereals and which are from the group consisting of

B1) fenoxaprop, fenoxaprop-P

-   -   (±)-2-[4-(6-chloro-1,3-benzoxazol-2-yloxy)phenoxy]-propionic        acid,    -   which embraces, inter alia, the use form fenoxapropethyl, ethyl,

-   -   (R)-2-[4-(6-chloro-1,3-benzoxazol-2-yloxy)phenoxy]propionic        acid,    -   which embraces, inter alia, the most frequent use form        fenoxaprop-P-ethyl,    -   the abovementioned compounds B1) being known from Pesticide        Manual, 10th Edition 1994, pp. 439–441 and 441–442,        B2) isoproturon

-   -   3-(4-isopropylphenyl)-1,1-dimethylurea, Pesticide Manual, 10th        Edition 1994, pp. 611–612,        B3) diclofop

-   -   (RS)-2-[4-(2,4-dichlorophenoxy)phenoxy]propionic acid, which        embraces, inter alia, the methyl ester, i.e. diclofop-methyl, as        the most important use form,    -   Pesticide Manual, 10th Edition 1994, pp. 315–317;        B4) clodinafop,

-   -   (R)-2-[4-(5-chloro-3-fluoro-2-pyridyloxy)phenoxy]propionic acid,    -   which embraces, in particular, also the use form        clodinafop-propargyl,    -   Pesticide Manual, 10th Edition 1994, pp. 216–217,        B5) mixtures of B4) and    -   cloquintocet,

-   -   (5-chloroquinolin-8-yloxy) acetic acid,    -   which is also employed as cloquintocet-mexyl and is a        particularly preferred safener for B4),    -   Pesticide Manual, 10th Edition 1994, pp. 226–227,        B6) chlortoluron

-   -   3-(3-chloro-p-tolyl)-1,1-dimethylurea    -   Pesticide Manual, 10th Edition 1994, pp. 195–196,        B7) methabenzthiazuron

-   -   1-(1,3-benzothiazol-2-yl)-1,3-dimethylurea Pesticide Manual,        10th Edition 1994, pp. 670–671,        B8) imazamethabenz

-   -   Reaction product comprising    -   (±)-6-(4-isopropyl-4-methyl-4-oxo-2-imidazolin-2-yl)-m-toluic        acid and        (±)-6-(4-isopropyl-4-methyl-4-oxo-2-imidazolin-2-yl)-p-toluic        acid,    -   it also being possible to apply the respective methyl esters,        which are known as imazamethabenzmethyl,    -   Pesticide Manual, 10th Edition 1994, pp. 582–584,        B9) tralkoxydim

-   -   2-[1-(ethoxyimino)propyl]-3-hydroxy-5-mesitylcyclohex-2-enone    -   Pesticide Manual, 10th Edition 1994, pp. 995–996,        B10) difenzoquat,

-   -   1,2-dimethyl-3,5-diphenylpyrazolium    -   for example also as difenzoquat metilsulfate, Pesticide Manual,        10th Edition 1994, pp. 330–331        B11) flamprop, flamprop-M,

-   -   N-benzoyl-N-(3-chloro-4-fluorophenyl)-DL-alanine        N-benzoyl-N-(3-chloro-4-fluorophenyl)-D-alanine comprising,        inter alia, also flamprop-methyl, flamprop-M-methyl and        flamprop-M-isopropyl, Pesticide Manual, 10th Edition 1994, pp.        464–465 and 466–468        and        B12) pendimethalin

-   -   N-(1-ethylpropyl)-2,6-dinitro-3,4-xylidine Pesticide Manual,        10th Edition 1994, pp. 779–780

The compounds B1) to B12) are herbicides which are known, for example,from the literature indicated for the compound in question and which actselectively against grasses, specifically in cereals. Mention is madenot only of the basic substance, whose formula is also indicatedregularly for illustration purposes, but also of conventionally employedvariations of the basic substances. For example B4) (clodinafop) isconventionally employed in the form of the propargyl ester and diclofop(B3)) as the methyl ester etc. If optically active forms of the type Bcompounds are customary, reference was also made of these forms (forexample, inter alia, fenoxaprop-ethyl and fenoxaprop-P-ethyl etc.)

The compounds B1), B3) and B4) belong to the chemical class of the2-(4-aryloxyphenoxy)propionic acids or to the ester derivatives. B2),B6) and B7) are ureas, while B8) is a representative of theimidazolinones, B9) a cyclohexanedione oxime, B11) an arylalanine andB12) a 2,6-dinitroaniline. Even though the representatives of this groupvary quite considerably indeed with regard to their chemical structures,they nevertheless form a joint subgroup on the basis of their spectrumof action and because of the fact that they represent synergists for thecompounds of the formula I.

In a further preferred embodiment of the invention, the herbicidallyactive combinations comprise, as type B herbicides, one or moreherbicides which act selectively predominantly against grasses in maizeand which are the group consisting of

B13) nicosolfuron

-   -   1-(4,6-dimethoxypyrimidin-2-yl)-3-(3-dimethylcarbamoyl-2-pyridylsulfonyl)urea    -   Pesticide Manual, 10th Edition 1994, pp. 734–735,        B14) rimsulfuron

-   -   1-(4,6-dimethoxypyrimidin-2-yl)-3-(3-ethylsulfonyl-2-pyridylsulfonyl)        urea    -   Pesticide Manual, 10th Edition 1994, pp. 904–905        and        B15) primisulfuron

-   -   2-[4,6-bis        (difluoromethoxy)pyrimidin-2-ylcarbamoylsulfamoyl]benzoic acid,        which is predominantly employed as primisulfuron-methyl,    -   Pesticide Manual, 10th Edition 1994, pp. 829–830.

The abovementioned compounds B13) to B15) belong to the chemical groupof the sulfonylureas. They differ structurally from the sulfonylureas ofthe formula I.

Particularly advantageous mixtures within the scope of the inventionresult when the combination according to the invention comprises, astype B compounds, diclofopmethyl, fenoxaprop-P-ethyl, isoproturon,mixtures of clodinafop-propargyl with cloquintocet-mexyl (known underthe registered trademark Topik®), imazamethabenz-methyl, nicosulfuronand/or rimsulfuron.

Other compositions which are part of the invention are those whichcomprise type B herbicides from subgroup Bb). Particularlyadvantageously herbicides which act selectively against dicots incereals and/or in maize are one or more herbicides from the group whichembraces aryloxyalkylcarboxylic acids, hydroxybenzonitriles, diphenylethers, azoles and pyrazoles, diflufenican and bentazone.

Herbicides which are preferred amongst the aryloxyalkyl carboxylic acidswhich are possible are, in turn, those selected from the groupconsisting of

B16) mecoprop, mecoprop-P

-   -   (RS)-2-(4-chloro-o-tolyloxy)propionic acid,    -   (R)-2-(4-chloro-o-tolyloxy)propionic acid,    -   Pesticide Manual, 10th Edition 1994, pp. 646–647 and 647–648,        B17) MCPA

-   -   (4-chloro-2-methylphenoxy) acetic acid,    -   predominantly employed forms being, inter alia, MCPA-butotyl,        MCPA-dimethylammonium, MCPA-iso-octyl, MCPA-potassium and        MCPA-sodium,    -   Pesticide Manual, 10th Edition 1994, pp. 638–640,        B18) dichlorprop, dichlorprop-P

-   -   (RS)-2-(2,4-dichlorophenoxy)propionic acid,    -   (R)-2-(2,4-dichlorophenoxy)propionic acid,    -   other forms which are used being, inter alia,        dichlorprop-butotyl, dichlorprop-ethylammonium,        dichlorprop-iso-octyl and dichlorprop-potassium, Pesticide        Manual, 10th Edition 1994, pp. 309–311 and 311–312,        B19) 2,4-D

-   -   (2,4-dichlorophenoxy)acetic acid,    -   frequently employed forms: 2,4-D-butotyl, 2,4-D-butyl,        2,4-D-dimethylammonium, 2,4-D-diolamine, 2,4-D-iso-octyl,        2,4-D-isopropyl and 2,4-D-trolamine, Pesticide Manual, 10th        Edition 1994, pp. 271–273,        B20) dicamba

-   -   3,6-dichloro-o-anisic acid    -   applied, inter alia, in the form of dicamba-dimethylammonium,        dicamba-potassium, dicamba-sodium and dicamba-trolamine,    -   Pesticide Manual, 10th Edition 1994, pp. 298–300 and        B21) fluroxypyr

-   -   4-amino-3,5-dichloro-6-fluoro-2-pyridyloxyacetic acid,    -   other use form: fluroxypyr-meptyl, Pesticide Manual, 10th        Edition 1994, pp. 505–507.

Also of particular interest are herbicidal compositions comprisinghydroxybenzonitriles which act selectively against dicots in cerealsand/or maize. These preferably include

B22) ioxynil

-   -   4-hydroxy-3,5-di-iodobenzonitrile,    -   frequent use forms: ioxynil-octanoate and ioxynil-sodium,    -   Pesticide Manual, 10th Edition 1994, pp. 598–600 and        B23) bromoxynil

-   -   3,5-dibromo-4-hydroxy-benzonitrile,    -   frequently employed as bromoxynil-octanoate and        bromoxynil-potassium,    -   Pesticide Manual, 10th Edition 1994, pp. 121–123.

Other advantageous compositions according to the invention aredistinguished by the fact that they comprise, as type B) herbicides, oneor more diphenyl ethers which act selectively against dicots in cerealsand/or maize and which are selected from amongst the herbicides

B24) bifenox

-   -   methyl-5-(2,4-dichlorophenoxy)-2-nitrobenzoate, Pesticide        Manual, 10th Edition 1994, pp. 94–96,        B25) fluoroglycofen

-   -   O-[5-(2-choro-α,α,α-trifluoro-p-tolyloxy)-2-nitrobenzoyl]glycolic        acid,    -   other use form: Fluoroglycofen-ethyl,    -   Pesticide Manual, 10th Edition 1994, pp. 492–494,        B26) acifluorfen

-   -   5-(2-chloro-α,α,α-trifluoro-p-tolyloxy)-2-nitrobenzoic acid,    -   also used in the form of acifluorfen-sodium, Pesticide Manual,        10th Edition 1994, pp. 12–13,        B27) lactofen

-   -   Ethyl        O-[5-(2-chloro-α,α,α-trifluoro-p-tolyloxy)-2-nitrobenzoyl]-DL-lactate,    -   Pesticide Manual, 10th Edition 1994, pp. 623,        B28) fomesafen

-   -   5-(2-chloro-α,α,α-trifluoro-p-tolyloxy)-N-methylsulfonyl-2-nitrobenzamide,    -   also employed in the form of fomesafen-sodium, Pesticide Manual,        10th Edition 1994, pp. 520–521 and        B29) oxyfluorfen

-   -   2-chloro-α,α,α-trifluoro-p-tolyl 3-ethoxy-4-nitro-phenyl ether,    -   Pesticide Manual, 10th Edition 1994, pp. 764–765.

Also of particular interest are furthermore herbicidal compositionswhich comprise, as type B compound, one or more azoles and pyrazoleswhich act selectively against dicots in cereals and/or maize and whichare selected from the group consisting of the herbicides

B30) ET-751

-   -   ethyl        2-chloro-5-(4-chloro-5-difluoromethoxy-1-methylpyrazol-3-yl)-4-fluorophenoxyacetate        Pesticide Manual, 10th Edition 1994, pp. 400 and        B31) azoles of the formula II

where

R¹ is (C₁–C₄) alkyl, R² is (C₁–C₄) alkyl, (C₁–C₄) alkylthio or (C₁–C₄)alkoxy, it being possible for each radical to be substituted by one ormore halogen atoms, or R¹ and R² together form the group (CH₂)_(m) wherem = 3 or 4, R³ is hydrogen or halogen, R⁴ is hydrogen or (C₁–C₄) alkyl,R⁵ is hydrogen, nitro, cyano or one of the groups —COOR⁷, —C(═X)NR⁷R⁸ or—C(═X)R¹⁰, R⁶ is hydrogen, halogen, cyano, (C₁–C₄)- alkyl, (C₁–C₄)alkylthio or —NR¹¹R¹², R⁷ and R⁸ are identical or different and arehydrogen or (C₁–C₄) alkyl, or R⁷ and R⁸ together with the nitrogen towhich they are bonded form a saturated 5- or 6-membered carbocyclicring, R¹⁰ is hydrogen or (C₁–C₄) alkyl, it being possible for the latterto be optionally substituted by one or more halogen atoms, and R¹¹ andR¹² are identical or different and are hydrogen, (C₁–C₄) alkyl or(C₁–C₄)- alkoxycarbonyl, it being possible for R¹¹ and R¹² together withthe nitrogen to which they are bonded to form a 3-, 5- or 6- memberedcarbocyclic or aromatic ring in which one carbon atom can optionally bereplaced by an oxygen atom;

-   -   the azoles of the formula II being disclosed, inter alia, in WO        94/08999.

Also preferred as type B compound is

B32) diflufenican

-   -   2′ 4′-difluoro-2-(α,α,α-trifluoro-m-tolyloxy)nicotinanilide    -   Pesticide Manual, 10th Edition 1994, pp. 335–336.

A further advantageous embodiment of the invention is characterized inthat a herbicidal composition comprises, as type B herbicide,

B33) bentazone

-   -   3-isopropyl-1H-2,1,3-benzothiadiazin-4 (3H)-one 2,2-dioxide,    -   Pesticide Manual, 10th Edition 1994, pp. 90–91.

A further advantageous embodiment of the invention is characterized inthat a herbicidal composition comprises, as type B herbicide, phenylpropionates such as

B51) carfentrazone

B52) carfentrazone-ethyl

Very particularly suitable as component in a herbicidal compositionaccording to the invention are, amongst the type B compounds which areselective in cereals and/or maize and active against dicots {subgroupBb) comprising of the herbicidally active substances B16)-B33) and theircustomary derivatives}, MCPA, mecoprop, dicamba, fluroxypyr,diflufenican, ioxynil and/or fluoroglycofen.

A third subgroup of compounds whose admixture with type A compoundspermits herbicidal compositions with outstanding characteristics to beobtained is subgroup Bc) of the herbicides which act selectively againstgrasses and dicots in cereals and/or maize. Type B substances with thisprofile of action are predominantly found in the chemical classes of thetriazine derivatives, chloroacetanilides and sulfonylureas, which differfrom the sulfonylureas given in formula I.

Preferred representatives are, inter alia, those which can predominantlybe employed selectively against grasses and dicots in cereals and, ifappropriate, in maize. These include, especially, the herbicidallyactive triazine derivatives and chloroacetanilides selected from thegroup consisting of the active substances B34) metolachlor

-   -   2-chloro-6′-ethyl-N-(2-methoxy-1-methylethyl) acet-o-toluidid,    -   Pesticide Manual, 10th Edition 1994, pp. 693–694,        B35) metribuzin

-   -   4-amino-6-tert-butyl-4,5-dihydro-3-methylthio-1,2,4-triazin-5-one    -   Pesticide Manual, 10th Edition 1994, pp. 699–700,        B36) atrazine

-   -   6-chloro-N-²-ethyl-N-4-isopropyl-1,3,5-triazine-2,4-diamine    -   Pesticide Manual, 10th Edition 1994, pp. 51–52,        B37) terbuthylazine

-   -   N² tert-butyl-6-chloro-N-⁴-ethyl-1,3,5-triazine-2,4-diamine,    -   Pesticide Manual, 10th Edition 1994, pp. 960–961,        B38) alachlor

-   -   2-chloro-2′,6′-diethyl-N-methoxymethylacetanilide, Pesticide        Manual, 10th Edition 1994, pp. 21–22 and        B39) acetochlor

-   -   2-chloro-N-ethoxyethyl-6′-ethyl) acet-o-toluidid Pesticide        Manual, 10th Edition 1994, pp. 10–11.

In an advantageous embodiment, the herbicidal compositions of theinvention also exhibit, as type B component, one or more sulfonylureaswhich act selectively in cereals against grasses and dicots and, ifappropriate, selectively in maize against grasses and dicots and whichdiffer from the type A compounds.

Particularly preferred sulfonylureas of this type are, inter alia,

B40) amidosulfuron

-   -   1-(4,6-dimethoxypyrimidin-2-yl)-3-mesyl (methyl)-sulfamoylurea,    -   Pesticide Manual, 10th Edition 1994, pp. 34–35,        B41) metsulfuron

-   -   2-(4-methoxy-6-methyl-1,3,5-triazin-2-ylcarbamoyl-sulfamoyl)benzoic        acid,    -   conventionally employed in the form of metsulfuronmethyl,    -   Pesticide Manual, 10th Edition 1994, pp. 701–702,        B42) tribenuron

-   -   2-[4-methoxy-6-methyl-1,3,5-triazin-2-yl(methyl)        carbamoylsulfamoyl]benzoic acid,    -   conventionally employed in the form of tribenuron-methyl,    -   Pesticide Manual, 10th Edition 1994, pp. 1010–1011,        B43) thifensulfuron

-   -   3-(4-methoxy-6-methyl-1,3,5-triazin-2-ylcarbamoylsulfamoyl)        thiophene-2-carboxylic acid,    -   usually used in the form of thifensulfuron-methyl, Pesticide        Manual, 10th Edition 1994, pp. 976–978,        B44) triasulfuron

-   -   1-[2-(2-chloroethoxy)        phenylsulfonyl]-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea,    -   Pesticide Manual, 10th Edition 1994, pp. 1005–1006,        B45) chlorsulfuron

-   -   1-(2-chlorophenylsulfonyl)-3-(4-methoxy-6-methyl-1,2,5-triazin-2-yl)urea,    -   Pesticide Manual, 10th Edition 1994, pp. 203–205,        B46) prosulfuron or CGA-152005

-   -   1-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-3-[2-(3,3,3-trifluoropropyl)phenylsulfonyl]urea,    -   Pesticide Manual, 10th Edition 1994, pp. 865–866, and/or        B47) Sulfonylureas of the formula III

-   -   in which

R¹ is methyl, ethyl, n-propyl, i-propyl or allyl, R² is CO—R⁵, COOR⁶,CO—NR⁸R⁹, CS—NR¹⁰R¹¹, SO₂R¹⁴ or SO₂NR¹⁵R¹⁶, R³ is COR¹⁷, COOR¹⁸,CONR¹⁹R²⁰ or CO—ON═CR²²R²³, R⁴ is hydrogen or (C₁–C₄) alkyl, R⁵ ishydrogen, (C₁–C₄) alkyl, (C₁—C₂) halo- alkyl, cyclopropyl, phenyl,benzyl or heteroaryl having 5 or 6 ring atoms, the last-mentioned 3radicals being unsubstituted or substituted by one or more halogenatoms, R⁶ is (C₁–C₄) alkyl, allyl, propargyl or cyclopropyl, R⁸ ishydrogen, (C₁–C₄) alkyl, (C₁–C₄) halo- alkyl or (C₁–C₄-alkoxy) carbonyl,R⁹—R¹¹ independently of one another are l identical or different and areH or (C₁–C₄) alkyl, R¹⁴ is (C₁–C₄) alkyl, R¹⁵ and R¹⁶ independently ofone another are identical or different and are hydrogen or (C₁–C₄)alkyl, R¹⁷ is hydrogen, (C₁–C₄) alkyl, (C₁–C₄) halo- alkyl, (C₃–C₆)cycloalkyl, phenyl or heteroaryl, the last-mentioned two radicals beingunsubstituted or substituted, R¹⁸ is hydrogen, (C₁–C₄) alkyl, (C₂–C₆)-alkenyl or (C₂–C₆) alkynyl, the last- mentioned three radicals beingunsub- stituted or substituted by one or more radicals selected from thegroup con- sisting of halogen, (C₁–C₄) alkoxy, (C₁–C₄) alkylthio andNR³¹R³², or is (C₃–C₆) cycloalkyl or (C₃–C₆) cycloalkyl- (C₁–C₃) alkyl,R¹⁹ is analogous to R⁸, R²⁰ is analogous to R⁹, R²² and R²³independently of one another are identical or different and are hydrogenor (C₁–C₂) alkyl, R³¹ and R³² independently of one another are identicalor different and are hydrogen or (C₁–C₄) alkyl, W is oxygen or sulfur, Xis (C₁–C₄) alkyl, (C₁–C₄) alkoxy, (C₁–C₄)- haloalkyl, (C₁–C₄) alkylthio,halogen or mono- or di(C₁–C₂-alkyl) amino, Y is (C₁–C₄) alkyl, (C₁–C₄)alkoxy, (C₁–C₄)- haloalkyl or (C₁–C₄) alkylthio, and Z is CH or N.

-   -   The sulfonylureas of the formula III are disclosed in WO        94/10154.

In yet another preferred embodiment, the herbicidal compositions of theinvention furthermore exhibit, as type B component,

B48) K1H-2023

-   -   Sodium 2,6-bis[(4,6-dimethoxypyrimidin-2-yl)oxy]-benzoate,    -   Pesticide Manual, 10th Edition 1994, pp. 620.

Very particularly suitable as component of a herbicidal compositionaccording to the invention amongst the type B compounds which areselective in cereals and/or maize and act against grasses and dicots{subgroup Bc) comprising the herbicidally active substances B34)–B48)and their customary derivatives} are atrazine, metsulfuron-methyl,tribenuron-methyl and/or amidosulfuron.

A fourth subgroup of compounds whose admixture with type A compoundsallows herbicidal compositions with superadditive activity to beobtained is subgroup Bd) of the herbicides which are active againstgrass weeds and broad-leaved weeds and are non-selective in non-cropareas and/or selective in transgenic cultures. Type B substances whichare thus described are, inter alia,

B49) glufosinate, glufosinate-P

-   -   4-[hydroxy(methyl)phosphinoyl]-DL-homoalanine,    -   4-[hydroxy(methyl)phosphinoyl]-L-homoalanine,    -   which are in each case preferably used in the form of        glufosinate-ammonium or glufosinate-P-ammonium, Pesticide        Manual, 10th Edition 1994, pp. 541–542 and/or        B50) glyphosate

-   -   N-(phosphonomethyl)glycine,    -   which is preferably employed in the form of        glyphosate-isopropylammonium,    -   glyphosate-sesquisodium and glyphosate-trimesium, Pesticide        Manual, 10th Edition 1994, pp. 542–544.

Combinations of the active substances A+B show superadditive effects,i.e. the herbicidal compositions according to the invention allow therate of application to be reduced and/or the safety margin especially incereals and/or maize crops to be increased while retaining equally goodcontrol of the harmful plants. Achieving both makes sense economicallyand ecologically. The choice of the amounts of components A+B to beemployed, the ratio of component A: component B and the order in time inwhich the components are applied depend on a wide variety of factors, asdoes, for example, the formulation to be selected. Not insignificant inthis context are, inter alia, the type of the components in the mixture,the development stage of the broad-leaved or grass weeds, the weedspectrum to be controlled, environmental factors, climatic conditions,soil conditions etc.

In a very particularly preferred embodiment according to the invention,herbicidal compositions according to the invention are characterized inthat they exhibit a synergistically active content of combination of thecompounds of the formula I or salts thereof (type A compounds) withcompounds from group B. It must be emphasized, in particular, that evenin combinations with rates of application or weight ratios of A:B wheresynergism cannot be detected easily in each case—for example because theindividual compounds are usually employed in the combination in verydifferent rates of application or else because control of the harmfulplants is already very good as a result of the individual compounds—asynergistic action is, as a rule, inherent in the herbicidalcompositions of the invention.

As already mentioned, the weight ratios A:B of the combined herbicides,and also their rates of application, can vary within wide limits.Preferred compositions within the scope of the invention are those whichcomprise compounds of the formula I or salts thereof (type A compounds)and compounds from group B in a weight ratio of 1:2500 to 20:1.

The following weight ratios are preferably employed:

Mixing ratios A:B Type B compounds standard preferred Ba) 1:500 to 1:11:200 to 1:2 Grass herbicides in cereals {e.g. B1)–B12)} Ba) 1:30 to 8:11:10 to 1:1 Grass herbicides in maize {e.g. B13)–B15)} Bb) 1:1500 to 1:11:500 to 1:10 Dicot herbicides in cereals and maize {e.g. B16)–B21)} Bb)1:500 to 1:1 1:200 to 1:3 Dicot herbicides in cereals and maize {e.g.B22) and B23)} Bb) 1:500 to 8:1 1:300 to 2:1 Dicot herbicides in cerealsand maize {e.g. B24)–B29)} Bb) 1:20 to 20:1 1:10 to 10:1 Dicotherbicides in cereals and maize {e.g. B30) and B31)} Bb) 1:250 to 1:11:100 to 1:3 Dicot herbicides in cereals and maize {e.g. B32)} Bb)1:2500 to 1:5 1:2000 to 1:10 Dicot herbicides in cereals and maize {e.g.B33)} Bc) 1:2500 to 1:2 1:2000 to 1:4 Grass and dicot herbicides incereals and/or maize {e.g. B34)–B39)} Bc) 1:40 to 20:1 1:20 to 10:1Grass and dicot herbicides in cereals and/or maize {e.g. B30)–B48)} Bd)1:1500 to 1:2 1:1000 to 1:10 Broad - spectrum herbicides which arenon-selective, or only selective in transgenic crops {e.g. B49) to B50)}

The rates of application of herbicide A in the active substancecombinations according to the invention are between 0.1 and 100 g ofa.i./ha (a.i.=active ingredients, i.e. rate of application based on theactive substance), preferably between 2 and 40 g of a.i./ha.

As a rule, the rates of application of type B compounds in the mixturesaccording to the invention are:

Rates of application in g of a.i./ha Type B compounds standard preferredBa) l 10 to 4000  50 to 1000 Grass herbicides in cereals {e.g. B1)–B12)}Ba) 5 to 60 5 to 30 Grass herbicides in maize {e.g. B13)–B15)} Bb)  50to 3000 100 to 2000 Dicot herbicides in cereals and maize {e.g.B16)–B21)} Bb)  50 to 1000 100 to 500  Dicot herbicides in cereals andmaize {e.g. B22) and B23)} Bb)  5 to 1000 10 to 500 Dicot herbicides incereals and maize {e.g. B24)–B29)} Bb) 3 to 25 5 to 20 Dicot herbicidesin cereals and maize {e.g. B30) and B31)} Bb) 50 to 500 100 to 250 Dicot herbicides in cereals and maize {e.g. B32)} Bb) 500 to 2500 750 to2000 Dicot herbicides in cereals and maize {e.g. B33)} Bc) 100 to 5000250 to 2500 Grass and dicot herbicides in cereals and/or maize {e.g.B34)–B39)} Bc) 2 to 80 5 to 50 Grass and dicot herbicides in cerealsand/or maize {e.g. B40)–B48)} Bd) 100 to 3000 100 to 1000 Broad -spectrum herbicides which are non-selective, or only selective intransgenic crops {e.g. B49) and B50)}

The active substance combinations according to the invention can existeither as mixed formulations of the two components, which are thenapplied in the customary manner in the form of a dilution with water, orelse prepared as so-called tank mixes by joint dilution with water ofthe components which are formulated separately.

The active substances of types A and B can be formulated in variousways, depending on the prevailing biological and/or chemico-physicalparameters. Suitable formulations which are possible are, for example:

wettable powders (WP), emulsifiable concentrates (EC), water-solublepowders (SP), water-soluble concentrates (SL), concentrated emulsions(BW) such as oil-in-water and water-in-oil emulsions, sprayablesolutions or emulsions, capsule suspensions (CS), oil- or water-baseddispersions (SC), suspoemulsions, suspension concentrates, dusts (DP),oil-miscible solutions (OL), seed-dressing products, granules (GR) inthe form of microgranules, spray granules, coated granules andadsorption granules, granules for soil application or broadcasting,water-soluble granules (SG), water-dispersible granules (WG), ULVformulations, microcapsules and waxes.

These individual types of formulations are known in principle and aredescribed, for example, in: Winnacker-Küachler, “Chemische Technologie”[Chemical Technology], Volume 7, C. Hauser Verlag Munich, 4th Edition1986; Wade van Valkenburg, “Pesticide Formulations”, Marcel Dekker N.Y.,1973; K. Martens, “Spray Drying Handbook”, 3rd Ed. 1979, G. Goodwin Ltd.London.

The formulation auxiliaries required, such as inert materials,surfactants, solvents and other additives are also known and aredescribed, for example, in: Watkins, “Handbook of Insecticide DustDiluents and Carriers”, 2nd Ed., Darland Books, Caldwell N.J.; H. v.Olphen “Introduction to Clay Colloid Chemistry”, 2nd Ed., J. Wiley &Sons, N.Y.; Marsden “Solvents Guide, 2nd Ed., Interscience, N.Y. 1963;McCutcheon's “Detergents and Emulsifiers Annual”, MC Publ. Corp.,Ridgewood N.J.; Sisley and Wood, “Encyclopedia of Surface ActiveAgents”, Chem. Publ. Co. Inc., N.Y. 1964; Schönfeldt,“Grenzflachenaktive Äthylenoxidaddukte” [Surface-active ethylene oxideadducts], Wiss. Verlagsgesellschaft, Stuttgart 1976; Winnacker-Küchler“Chemische Technologie” [Chemical Technology], Volume 7, C. HauserVerlag Munich, 4th Edition 1986.

Based on these formulations, it is also possible to prepare combinationswith other pesticidally active substances, herbicides, insecticides,fungicides and antidotes, safeners, fertilizers and/or growthregulators, for example in the form of readymix or a tank mix.

The herbicide combinations of the invention are particularlyadvantageously prepared by formulating the compounds of the formula I orsalts thereof (type A compounds) with one or more type B compoundsanalogously to a customary crop protection formulation from the groupcomprising water-soluble wettable powders (WP), waterdispersiblegranules (WDG), water-emulsifiable granules (WEG), suspoemulsions (SE)and oil suspension concentrates (SC).

Wettable powders are preparations which are uniformly dispersible inwater and which, besides the active substances, also comprise ionicand/or nonionic surfactants (wetting agents, dispersants), for examplepolyoxyethylated alkylphenols, polyoxyethylated fatty alcohols and fattyamines, fatty alcohol polyglycol ether sulfates, alkanesulfonates oralkylarylsulfonates, sodium lignosulfonate, sodium2,2′-dinaphthylmethane-6,6′-disulfonate, sodiumdibutylnaphthalenesulfonate or else sodium oleylmethyltauride, inaddition to a diluent or inert substance.

Emulsifiable concentrates are prepared by dissolving the activesubstance, or active substances, in an organic solvent, for examplebutanol, cyclohexanone, dimethylformamide, xylene or else higher-boilingaromatics or hydrocarbons with the addition of one or more ionic and/ornon-ionic surfactants (emulsifiers).

Examples of emulsifiers which can be used are: calciumalkylarylsulfonates, such as calcium dodecylbenzene sulfonate, ornon-ionic emulsifiers such as fatty acid polyglycol esters, alkylarylpolyglycol ethers, fatty alcohol polyglycol ethers, propyleneoxide/ethylene oxide condensates (for example block copolymers), alkylpolyethers, sorbitan fatty acid esters, polyoxyethylene sorbitan fattyacid esters or other polyoxyethylene sorbitan esters.

Dusts are obtained by grinding the active substance, or activesubstances, with finely divided substances, for example talc, naturalclays such as kaolin, bentonite and pyrophyllite, or diatomaceous earth.

Granules can be prepared either by spraying the active substance, oractive substances, on to adsorptive, granulated inert material or byapplying active substance concentrates to the surface of carriers suchas sand, kaolinites or granulated inert material with the aid ofbinders, for example polyvinyl alcohol, sodium polyacrylate or elsemineral oils. Water-dispersible granules are prepared, as a rule, by thecustomary processes such as spray drying, fluidized-bed granulation,disk granulation, mixing using high-speed mixers and extrusion withoutsolid inert material. Suitable active substances can also be granulatedin the manner which is customary for the preparation of fertilizergranules, if desired in the form of a mixture with fertilizers.

As a rule, the agrochemical preparations according to the inventioncomprise 0.1 to 99% by weight, in particular 2 to 95% by weight, ofactive substances of types A and B besides customary formulationauxiliaries.

The concentrations of the active substances A+B in the formulations canvary. In wettable powders, the active substance concentration is, forexample, approximately 10 to 95% by weight, the remainder to 100% beingcomposed of customary formulation components. In the case ofemulsifiable concentrates, the active substance concentration can befrom approximately 1 to 85% by weight, preferably 5 to 80% by weight.Formulations in the form of dusts comprise approximately 1 to 25% byweight, in most cases 5 to 20% by weight, of active substances,sprayable solutions approximately 0.2 to 25% by weight, preferably 2 to20% by weight, of active substances. In granules, such as dispersiblegranules, the active substance content depends partly on whether theactive compound is in liquid or solid form and on which granulationauxiliaries and fillers are used. As a rule, the content in thewater-dispersible granules is between 10 and 90% by weight.

Besides, the abovementioned active substance formulations comprise, ifappropriate, the adhesives, wetting agents, dispersants, emulsifiers,penetrants, preservatives, antifreeze agents, solvents, fillers,colorants, carriers, antifoams, evaporation inhibitors and pH- andviscosity-regulators which are customary in each case.

To increase the tolerance and/or selectivity of the herbicidecombinations according to the invention even further, it is advantageousto apply them together with safeners or antidotes, either jointly in amixture or at different points in time. The compounds which are suitableas safeners or antidotes for the combinations according to the inventionare, for example, disclosed in EP-A-333 131 (ZA-89/1960), EP-A-269 806(U.S. Pat. No. 4,891,057), EP-A-346 620 (AU-A-89/34951) and ininternational patents PCT/EP 90/01966 (WO-91/08202) and PCT/EP 90/02020(WO-91/078474) and in the literature cited therein or can be prepared byprocesses described in these publications.

Other suitable safeners are known from EP-A-94 349 (U.S. Pat. No.4,902,304), EP-A-191 736 (U.S. Pat. No. 4,881,966) and EP-A-0 492 366and from the literature cited in these publications. Particularlypreferred antidotes or safeners are, inter alia, compounds of thedichlorophenylpyrazoline-3-carboxylic acid type,dichlorophenylpyrazolecarboxylic acid derivatives, compounds of thetriazolecarboxylic acid type, compounds of the 5-benzyl-or,5-phenyl-2-isoxazoline-3-carboxylic acid type, compounds of the8-guinolineoxyacetic acid type, compounds of the(5-chloro-8-quinolinoxy)malonic acid type and active substances of thephenoxyacetic- or propionic acid derivative or aromatic carboxylic acidtype. All of the abovementioned compounds are described in EP-A-0 640587, to which reference is made for disclosure purposes. Theabovementioned application not only mentions the above-describedsafeners and antidotes for compounds of the formula I, but also mixtureswith standard herbicides. This application, however, lacks, on the onehand, a necessary individual enumeration of the compounds of the formulaI, since they are embraced by a very much broader formula in EP-A-0 640587, and, on the other hand, nothing is mentioned about the surprisingsuperadditive increase in action of the combinations disclosed in thepresent application.

For use, the formulations, which are in commercially available form,are, if appropriate, diluted in the customary manner, for example usingwater in the case of wettable powders, emulsifiable concentrates,dispersions and water-dispersible granules. Preparations in the form ofdusts, soil granules, granules for broadcasting and sprayable solutionsare conventionally not diluted further with other inert substances priorto use.

The invention also relates to a method of controlling undesirableplants, which comprises applying a herbicidally active amount of acombination according to the invention of active substances A+B to theseplants or to the area under cultivation. The active substances can beapplied to the plants, to parts of the plants, to seeds of the plants orto the area under cultivation. In a preferred variant of the method, thecompounds of the formula (I) or salts thereof (type A compounds) areapplied at rates of 0.1 to 100 g of a.i./ha, preferably 2 to 40 g ofa.i./ha, while the rates for the type B compounds are from 1 to 5000 gof a.i./ha. Application of the active substances of types A and Bsimultaneously or at separate points in time in a weight ratio of 1:2500to 20:1 is preferred. The joint application of the active substances inthe form of tank mixes is furthermore particularly preferred, theoptimally formulated concentrated formulations of the individual activesubstances are jointly mixed with water in the tank and the resultingspray mixture is applied.

Since the tolerance of the combinations according to the invention bycrops is extremely good while simultaneously controlling the harmfulplants to a very high degree, they can be regarded as selective. In apreferred embodiment, herbicidal compositions comprising the activesubstance combinations according to the invention are therefore employedfor selectively controlling undesirable plants. The method ofselectively controlling harmful plants when using the type B) componentsfrom subgroups Ba) to Bc) is particularly advantageous when theherbicidal compositions of the invention are employed in crops such ascereals, maize, rice, sugar cane, in plantation crops, in grassland orin pastures.

The type A components used by themselves pre-emergence or post-emergencein cereals, rice and maize, in non-crop areas and in plantation cropsalready control a fairly broad spectrum of annual and perennialbroad-leaved weeds, grass weeds and Cyperaceae.

The spectrum of action of the type A compounds is further improved bycombining them with the type B components mentioned in the invention.

Thus, the compounds B1) to B12) complement and enhance, inter alia, theaction when controlling grass weeds in cereals and, in some cases, alsothe action against broad-leaved weeds in cereals, in each case both pre-and post-emergence.

The sulfonylureas from subgroup Ba) (compounds B13) to B15)) are mainlyused for an even more efficient control of grass weeds and broad-leavedweeds, mainly post-emergence in maize.

The components B16) to B21) of the group Bb) are in most cases growthregulator herbicides, which improve the action of the type A compoundsin a large number of agricultural crops (preferably cereals and maize),especially when controlling broad-leaved weeds and Cyperaceae. They arepreferably employed post-emergence.

Compounds B22) and B23) are herbicidally active substances which mainlyimprove the efficacy of weed control in maize and cereals. In mostcases, they are employed post-emergence. The nitrodiphenyl ethers B24)to B29) are employed both pre- and post-emergence. They are used toimprove the efficacy in cereals, rice, maize, but also soya beans.

The azoles and pyrazoles from subgroup Bb) (e.g. B30) and B31)) can beemployed particularly advantageously at comparatively low rates in thepost-emergence control of dicotyledon weeds in cereals. B33) improvesthe spectrum of action of the combinations according to the inventionpre- and post-emergence when controlling weeds in cereals and other cropspecies, while B33) is a herbicidally active substance which is employedpost-emergence for controlling weeds in a large number of agriculturalcrop plants.

The triazines and chloroacetanilides from subgroup Bc) (e.g. B34) toB39)) are widely used active substances which can be employed both pre-and post-emergence for improving the efficacy of the type A compounds inthe control of grass weeds and broad-leaved weeds, especially in maize,but in some cases also in cereals, in non-crop areas or in plantationcrops.

Finally, compounds B40) to B48) (subgroup Bc)) are used, in theinvention, preferably for controlling broad-leaved is weeds—in somecases also grass weeds—in cereals and in some cases in maize but also inpotatoes, in grassland or in non-crop areas post-emergence, but in somecases also pre-emergence.

Depending on the nature of component B, the herbicidal combinationsaccording to the invention can advantageously be used for controllingundesirable plants even in non-crop areas and/or in transgenic cropssuch as maize, soya, cereals, rice and others. Particularly suitable forthis purpose are the components from group Bd).

In this context, the term non-crop areas not only embraces paths,squares, industrial complexes and rail-tracks which must regularly bekept free from weeds, rather, plantation crops also come under thisgeneric term within the scope of the invention. Accordingly, thecombinations according to the invention (especially those comprising thecomponents from subgroup Bd)), which control a wide spectrum of weedsranging from annual and perennial weeds such as, for example, Agropyron,Paspalum, Cynodon, Imperata via Pennisetum, Convolvulus and Cirsium toRumex and others can be applied for the selective control of harmfulplants in plantation crops such as oil palm, coconut palm, india-rubbertree, citrus, pineapple, cotton, coffee, cocoa and the like and also infruit growing and viticulture. Equally, the combinations according tothe invention can be employed in arable crops using the no-till orzero-till method. As already mentioned, however, they can also be usedin non-crop areas in the strict sense, i.e. non-selectively in paths,squares, etc., to keep these areas free from undesirable vegetation.However, the components from group Bd), which are non-selective per se,not only become selective herbicides when the tolerance of the cropplants is appropriate, but combinations according to the invention arealso selective when used in so-called transgenic crops. Transgenic cropsare plants which have been genetically manipulated to become resistantto herbicides which are non-selective per se. Such altered crop plantssuch as, for example, maize, cereals or soya beans, subsequently permitthe selective use of combinations with B49) or B50).

To conclude, it can be said that superadditive (=synergistic) effectsare observed when4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoicesters and/or salts thereof are used together with one or more activesubstances from group B. The activity in the combinations exceeds theactivity of the individual products when applied alone.

These effects permit

-   -   the rate of application to be reduced,    -   a broader spectrum of broad-leaved weeds and grass weeds to be        controlled,    -   more rapid and more reliable action,    -   longer long-term action,    -   complete control of the harmful plants with only one or few        applications, and    -   the application period of the active substances in combination        to be extended.

The abovementioned properties are required under realistic weed controlconditions to keep agricultural tracts free from undesirable competitorsand thus to safeguard, or increase, quality and quantity of the yields.The combinations according to the invention markedly exceed the priorart with regard to the above-described characteristics.

The examples which follow are intended to illustrate the invention:

1. FORMULATION EXAMPLES

-   a) A dust is obtained by mixing 10 parts by weight of an active    substance combination according to the invention and 90 parts by    weight of talc as inert substance and comminuting the mixture in a    hammer mill.-   b) A wettable powder which is readily dispersible in water is    obtained by mixing 25 parts by weight of active substances A+B, 64    parts by weight of kaolin-containing quartz as inert substance, 10    parts by weight of potassium lignosulfonate and 1 part by weight of    sodium oleoylmethyltaurinate as wetting agent and dispersant and    grinding the mixture in a pinned-disk mill.-   c) A dispersion concentrate which is readily dispersible in water is    obtained by mixing 20 parts by weight of active substances A+B with    6 parts by weight of alkylphenol polyglycol ether (®Triton X 207), 3    parts by weight of isotrideconol polyglycol ether (8 EO) and 71    parts by weight of paraffinic mineral oil (boiling range for example    approximately 255 to 277° C.) and grinding the mixture in a bowl    mill to a fineness of below 5 microns.-   d) An emulsifiable concentrate is obtained from 15 parts by weight    of cyclohexanone as the solvent and 10 parts by weight of    oxethylated nonylphenol as the emulsifier.-   e) Water-dispersible granules are obtained by mixing 75 parts by    weight of active substances A+B,    -   10 parts by weight of calcium lignosulfonate,    -   5 parts by weight of sodium lauryl sulfate,    -   3 parts by weight of polyvinyl alcohol and    -   7 parts by weight of kaolin,    -   grinding the mixture in a pinned-disk mill and granulating the        powder in a fluidized bed by spraying on water as the        granulation liquid.-   f) Water-dispersible granules are also obtained by homogenizing and    precomminuting, in a colloid mill, 25 parts by weight of active    substances A+B,    -   5 parts by weight of sodium        2,2′-dinaphthylmethane-6,6′-disulfonate,    -   2 parts by weight of sodium oleoylmethyltaurinate,    -   1 part by weight of polyvinyl alcohol,    -   17 parts by weight of calcium carbonate and    -   50 parts by weight of water, subsequently grinding the mixture        in a bead mill and atomizing and drying the resulting suspension        in a spray tower by means of a single-substance nozzle.-   g) Extruder granules are obtained by mixing 20 parts by weight of    active substances A+B, 3 parts by weight of sodium lignosulfonate, 1    part by weight of carboxymethylcellulose and 76 parts by weight of    kaolin, grinding the mixture and moistening it with water. This    mixture is extruded and subsequently dried in a stream of air.

2. BIOLOGICAL EXAMPLES

The examples given below were performed in the greenhouse and, in somecases, in field trials.

Field Trials

The herbicides, or combinations, were applied in cereals after the weedshad emerged naturally using plot sprayers. After application, theresults, such as damage to the crop plants and effect on broad-leavedweeds/grass weeds were assessed by means of visual scoring. Theherbicidal action was assessed qualitatively and quantitatively bycomparing untreated and treated plots on the basis of the effect onplant growth and the development of chloroses and necroses down to thecomplete destruction of the weeds (0–100%). The application was effectedwhen the crop plants and weeds were in the 2–4 leaf stage. The test wasevaluated approximately 4 weeks after application.

Greenhouse Experiments

In the greenhouse experiments, the crop plants and broadleavedweeds/grass weeds were grown in No. 13 pots and treated in the 2–4 leafstage. The pots were subsequently placed in the greenhouse under goodgrowth conditions (temperature, atmospheric humidity, water supply).

The assessments were carried out similarly to those in the field trials,i.e. visual scoring of the treated plants in comparison with untreatedcontrol variants. These assessments were carried out 3 weeks afterapplying the test preparations and their combinations. The experimentshad been set up in two replications.

Assessment of the Combination Effects in the Examples

To assess the combination effects, the activities of the individualcomponents were added and compared with the activity of the mixtures inequal doses. It was frequently observed that the efficacies of thecombinations exceeded the total of the individual activities.

In cases with less clear effects, the expected value was calculatedusing Colby's formula and compared with the empirically determinedresult. The calculated efficacy of a combination which is expected intheory is determined is using S.R. Colby's formula:“Calculation of synergistic and antagonistic responses of herbicidecombinations”, Weeds 15 (1967), pages 20 to 22.

In the case of two-way combinations, this formula reads:

$E = {X + Y - \frac{X \cdot Y}{100}}$and in the case of the combination of three herbicidally activesubstances, analogously:

$E = {X + Y + Z + \frac{X \cdot Y \cdot Z}{10000} - \frac{{XY} + {XZ} + {YZ}}{100}}$where

-   X=% damage caused by herbicide A at a rate of ×kg a.i./ha;-   Y=% damage caused by herbicide B at a rate of y kg a.i./ha;-   Z=% damage caused by a further herbicide C at a rate of z kg    a.i./ha;-   E=expected value, i.e. expected damage caused by herbicides A+B (or    A+B+C) at x+y (or x+y+z) kg a.i./ha.

Synergistic effects were assumed to be when the empirical value exceededthe expected value. In the case of combinations with individualcomponents with the same active substances, comparisons via the totalformula were also possible.

However, in most cases, the synergistically increased action is sopronounced that Colby's criterium can be dispensed with; in this case,the activity of the combination clearly exceeds the formal (numerical)total of the activities of the individual substances.

Particular mention must be made of the fact that an assessment of thesynergism in the active substances employed must take into considerationthe great differences in rates in which the individual active substancesare applied. Thus, it does not make sense to compare the activities ofthe active substance combinations and the individual active substancesat in each case identical application rates. Other savings according tothe invention in the amount of active substance only become apparentfrom the superadditive increase in action when using combined rates orfrom the reduction in the rates of the two individual active substancesin the combinations in comparison with the individual active substanceswhile achieving identical effects in each case.

TABLE 1 g of PHACA APESV TRZAW Active substance(s) a.i./ha % control %damage A)  3  0 85 0  5 15 93 0  10 35 97 0  20 53 98 0 B3) 225  0  0 0450  0  0 0 900  0  8 0 A) + B3)  3 + 450 90 (0 + 0) 97 (85 + 0) 0  5 +450 90 (15 + 0) 97 (93 + 0) 0 PHACA = Phalaris canariensis APESV = Aperaspica venti TRZAW = Triticum aestivuml A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB3) = diclofop-methyl ( ) = % efficacy of individual active substances

TABLE 2 g of LOLMU PHACA TRZAW Active substance(s) a.i./ha % control %damage A)  3  0  0 0  5  5 15 0 10 10 35 0 20 48 53 0 B1) 18  0  0 0 37 0  0 0 75  8 60 0 A) + B1)  3 + 37 58 (0 +0) 88 (0 + 0) 0  5 + 37 83(5 + 0) 97 (15 + 0) 0 10 + 37 85 (10 + 0) 99 (35 + 0) 0 B5) 10  0  0 020  0  0 0 40  5  5 0 A) + B5)  3 + 20 75 (0 + 0) 70 (0 + 0) 0  5 + 2085 (5 + 0) 80 (15 + 0) 0 10 + 10 81 (10 + 0) 78 (35 + 0) 0 LOLMU =Lolium multiflorum PHACA = Phalaris canariensis TRZAW = Triticumaestivum A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB1) = Puma S ® = mixture of fenoxaprop-P-ethyl and the safenerfenchlorazole-ethyl =1-(2,4-dichlorophenyl)-5-(trichloromethyl-1H-1,2,4-triazole-3-carboxyethylester, ratio 2:1 B5) = Topik ® = mixture of clodinafop-propargyl and thesafener cloquintocet-methyl, ratio 4:1 ( ) = % efficacy of individualactive substances

TABLE 3 Active g of LOLMU PHACA TRZAW substance(s) a.i./ha % control %damage A)   3  0  0 0   5  5 15 0  10 10 35 0  20 48 53 0 B2)  375  0  00  750  0  0 0 1500  0 50 0 A) + B2)   3 + 1500 20 (0 + 0) 80 (0 + 50) 0  5 + 1500 43 (5 + 0) 85 (15 + 50) 0  10 + 1500 55 (10 + 0) 83 (35 + 50)0 B8)  375  0  0 0  750  0  0 0 1500 20 13 5 A) + B8)   3 + 750 93 (0 +0) 99 (0 + 0) 5  10 + 375 93 (10 + 0) 99 (35 + 0) 5 LOLMU = Loliummultiflorum PHACA = Phalaris canariensis TRZAW = Triticum aestivum A) =sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB2) = isoproturon (Arelon ® ) B8) = imazamethabenz-methyl (Assert ® ) () = % efficacy of individual active substances

TABLE 4 g of ECHCR ZEAMA Active substance(s) a.i./ha % control % damageA) 10 65 0 20 75 0 40 80 0 80 88 0 B13) 15 0 0 30 73 0 60 75 2 A) + B13)10 + 15 97 (65 + 0) 3 B14)  5 15 0 10 60 2 20 85 3 A) + B14) 10 + 5  80(65 + 15) 0 10 + 10 {70} 0 92 (65 + 60) {86} ECHCR = Echinochloa crusgalli ZEAMA = Zea mays A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB13) = nicosulfuron B14) = rimsulfuron ( ) = % efficacy of theindividual active substances { } = expected value using Colby's formula

TABLE 5 Active g of LOLMU FALCO TRZAW substance(s) a.i./ha % control %damage A) 2.5 68 73 0 5 75 85 0 10 83 88 0 20 97 10 40 98 15 80 99 18160 99 28 B17) 250 0 0 500 68 1000 75 A) + B17)  10 + 250 94 (88 + 0) 0 5 + 500 98 (85 + 68) 0 {95} B16) 125 0 0 250 15 0 500 55 0 1000 68 0A) + B16)  10 + 125 91 (88 + 0) 0 B20) 50 5 0 100 10 0 200 18 0 400 4010 A) + B20)  5 + 50 78 (75 + 5) 0  10 + 100 {76} 0 94 (93 + 10) {86}B21) 50 73 100 80 200 95 A) + B21)  5 + 100 99 {97} 0 10 + 50 98 {97} 0 10 + 100 100 {98} 0 LOLMU = Lolium multiflorum FALCO = Fallopiacolvolvulus TRZAW = Triticum aestivuml A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB17) = MCPA sodium salt B16) = mecoprop-P B20) = dicamba B21) =fluroxypyr (Starane ® ) ( ) = % efficacy of the individual activesubstances { } = expected value using Colby's formula

TABLE 6 g of CENCY SECCW Active substance(s) a.i./ha % control % damageA) 5 0 0 10 30 0 15 60 5 B16) 600 30 0 2500 70 0 A) + B16) 10 + 600 100(30 + 30) 0 CENCY = Centaurea cyanus SECCW = Secale cereale A) = sodiumsalt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB16) = mecoprop-P ( ) = % efficacy of the individual active substances

TABLE 7 Active g of GALAP VIOAR TRZAW substance(s) a.i./ha % control %damage A) 2.5 35 58 0 5 58 75 0 10 60 95 2 20 99 98 10 B22) 62.5 0 0 1253 0 250 10 0 500 18 0 A) + B22) 10 + 125 68 (60 + 3) 0 10 + 250 85 (60 +10) 0 B25) 4 3 0 8 18 0 15 38 0 30 62 0 A) + B25) 5 + 15 93 (75 + 38) 0{85 } B32) 13 0 0 25 0 0 50 5 0 100 5 0 A) + B32) 10 + 13   98 (60 + 0)0 LOLMU = Lolium multiflorum VIOAR = Viola arvensis TRZAW = Triticumaestivum A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB32) = ioxynil B25) = fluoroglycofen-ethyl (Compete ® ) B32) =diflufenican ( ) = % efficacy of the individual active substances { } =expected value using Colby's formula

TABLE 8 g of ECHCR ZEAMA Active substance(s) a.i./ha % control % damageA) 10 65 0 20 73 0 40 80 0 80 88 0 B36) 375 0 0 750 0 0 1500 3 0 3000 30 A) + B36) 10 + 375 88 (65 + 0) 0 10 + 750 93 (65 + 0) 0 ECHCR =Echinochloa crus galli ZEAMA = Zea maysl A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB36) = atrazine ( ) = % efficacy of the individual active substances

TABLE 9 Active g of FALCO CENCY TRZAW substance(s) a.i./ha % control %damage A) 2.5 73 30 0 5 85 43 0 10 88 58 2 20 97 78 10 40 98 15 B41) 1 00 3 0 0 5 0 0 10 0 0 A) + B41) 2.5 + 3   50 (30 + 0) 0 5 + 3 75 (43 + 0)0 10 + 3  78 (58 + 0) 0 B42) 5 88 0 10 93 0 20 95 0 40 97 0 A) + B42)5 + 5 100 (85 + 88) 0 {98} CENCY = Centaurea cyanus FALCO = Fallopiaconvolvulus TRZAW = Triticum aestivum A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB41) = metsulfuron-methyl (Gropper ® ) B42) = tribenuron-llmethyl(Pointer ® ) ( ) = % efficacy of the individual active substances { } =Expected value using Colby's formula

TABLE 10 g of CENCY SECCW Active substance(s) a.i./ha % control % damageA) 5 0 0 10 30 0 15 60 5 B40) 20 25 0 A) + B40) 10 + 20 95 (30 + 25) 0CENCY = Centaurea cyanus SECCW = Secale cereale A) = sodium salt ofmethyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB40) = amidosulfuron ( ) = % efficacy of the individual activesubstances

TABLE 11 g of GALAP AVEFA MERAN Active substance(s) a.i./ha % control A)5 75 60 70 10 98 80 94 B49) 150 55 60 65 300 73 70 78 450 85 80 90 A) +B49) 5 + 150 99 (75 + 55) 90 (60 + 60) 98 (70 + 65)   {89}   {84}   {98}GALAP = Gallium aparine AVEFA = Avena fatua MERAN = Mercurialis annua A)= sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB49) = glufosinate-ammonium ( ) = % efficacy of the individual activesubstances { } = expected value using Colby's formula

The examples demonstrate that certain weeds can only be controlledthoroughly by the individual active substances when these are used athigh dosages. When applied at low dosages, the efficacy of thecomponents is, as a rule, only poor and falls far short of what isrequired under realistic conditions. Good effects against all weedspecies tested can only be achieved by applying the active substancesjointly. The additive efficacy of the individual components was exceededmarkedly, i.e. the control level required was achieved by markedly lowerrates of application. These effects widen the spectrum of actionmarkedly.

The compatibility with crops, which is assessed in the form of damage,is not adversely affected, i.e. the combinations can be considered fullyselective.

Other advantages and use forms of the invention can be seen from thepatent claims which follow.

TABLE 12 Active g of ABUTHE AMBEL ZEAMA substance(s) ai/ha % control %damage A) 2.5 10 88 3 B31) 4.5 60  0 5 A) + b52) 2.5 + 4.5 89(60 + 10)95(88 + 0) 7 ABUTHE = Abuthilon theophrastis AMBEL = Ambrosia elatiorZEAMA = Zea mays A) = sodium salt of methyl4-iodo-2-[3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)ureidosulfonyl]benzoateB52) = carfentrazone-ethyl:

(+) = % efficacy of the individual active substance(s) (additive method)

1. A synergistic herbicidal composition comprising synergisticallyeffective amounts of A) at least one compound from the group of thesubstituted phenylsulfonylureas of the formula I and theiragriculturally acceptable salts

 in which  R¹ is (C₁–C₈)alkyl  and B) at least one herbicidally activecompound from the group of compounds selected from the group consistingof Ba) one or more herbicides which act selectively against grasses incereals and/or maize selected from the group consisting of B8)imazamethabenz and imazamethabenz methyl

and Bb) one or more herbicides which act selectively against dicots incereals and/or maize selected from the group consisting of B16)mecoprop, mecoprop-P

B22) ioxynil

or ioxynil-octanoate or ioxynil-sodium, and B33) bentazone


2. The composition as claimed in claim 1, wherein for the compounds offormula (I) or salts thereof, R₁ is methyl, ethyl, n-propyl, isopropyl,n-, tert-, 2-butyl or isobutyl, n-pentyl, isopentyl, n-hexyl, isohexyl,1,3-dimethylbutyl, n-heptyl, 1-methylhexyl or 1,4-dimethylpentyl.
 3. Thecomposition as claimed in claim 1, wherein for the compounds of formula(I) or salts thereof, R₁ is methyl.
 4. The composition of claim 1,wherein the salts of the herbicide of the formula (I) are formed byreplacing the hydrogen of the —SO₂—NH— group by a cation selected fromthe group consisting of alkali metals, alkaline earth metals andammonium.
 5. The composition as claimed in claim 1, wherein the group Bherbicide is imazamethabenz, imazamethabenz methyl, mecoprop,mecoprop-P, ioxynil, or bentazone.
 6. The composition as claimed inclaim 1, which comprises 0.1 to 9% by weight of at least one compound offormula I or salts thereof and at least one group B herbicide.
 7. Thecomposition as claimed in claim 1, wherein the group B herbicide isimazamethabenz, imamazamethabenz methyl, mecoprop, mecoprop-P, orioxynil.
 8. The composition as claimed in claim 1, wherein the group Bherbicide is B33) bentazone


9. A method of controlling undesirable plants, which comprises applyingthe synergistic herbicidal composition according to claim 1 to saidundesirable plants or to an area under cultivation.
 10. The method asclaimed in claim 1, wherein the rate of application for the compounds offormula (I) or salts thereof is from 0.1 to 100 g of ai./ha and the ratefor the group B herbicide is from 1 to 5000 g of a.i./ha.
 11. The methodas claimed in claim 1, wherein the rate of application for the compoundof formula (I) or salts thereof is from 2 to 40 g of a.i./ha.
 12. Themethod according to claim 1, wherein said at least one compound offormula I or salts thereof and said at least one herbicide of group Bare applied in a weight ratio of 1:2500 to 20: 1, either simultaneouslyor at separate points in time.
 13. The method according to claim 1,wherein the synergistic herbicidal composition is employed in transgeniccrops, or in cereals, maize, rice, sugar cane, plantation crops,grasslands or pastures.
 14. The method according to claim 1, wherein thesynergistic herbicidal composition is for the selection control ofundesirable plants.